diff options
Diffstat (limited to 'include/crypto/if_alg.h')
-rw-r--r-- | include/crypto/if_alg.h | 170 |
1 files changed, 170 insertions, 0 deletions
diff --git a/include/crypto/if_alg.h b/include/crypto/if_alg.h index e2b9c6fe2714..75ec9c662268 100644 --- a/include/crypto/if_alg.h +++ b/include/crypto/if_alg.h @@ -20,6 +20,9 @@ #include <linux/types.h> #include <net/sock.h> +#include <crypto/aead.h> +#include <crypto/skcipher.h> + #define ALG_MAX_PAGES 16 struct crypto_async_request; @@ -68,6 +71,99 @@ struct af_alg_sgl { unsigned int npages; }; +/* TX SGL entry */ +struct af_alg_tsgl { + struct list_head list; + unsigned int cur; /* Last processed SG entry */ + struct scatterlist sg[0]; /* Array of SGs forming the SGL */ +}; + +#define MAX_SGL_ENTS ((4096 - sizeof(struct af_alg_tsgl)) / \ + sizeof(struct scatterlist) - 1) + +/* RX SGL entry */ +struct af_alg_rsgl { + struct af_alg_sgl sgl; + struct list_head list; + size_t sg_num_bytes; /* Bytes of data in that SGL */ +}; + +/** + * struct af_alg_async_req - definition of crypto request + * @iocb: IOCB for AIO operations + * @sk: Socket the request is associated with + * @first_rsgl: First RX SG + * @last_rsgl: Pointer to last RX SG + * @rsgl_list: Track RX SGs + * @tsgl: Private, per request TX SGL of buffers to process + * @tsgl_entries: Number of entries in priv. TX SGL + * @outlen: Number of output bytes generated by crypto op + * @areqlen: Length of this data structure + * @cra_u: Cipher request + */ +struct af_alg_async_req { + struct kiocb *iocb; + struct sock *sk; + + struct af_alg_rsgl first_rsgl; + struct af_alg_rsgl *last_rsgl; + struct list_head rsgl_list; + + struct scatterlist *tsgl; + unsigned int tsgl_entries; + + unsigned int outlen; + unsigned int areqlen; + + union { + struct aead_request aead_req; + struct skcipher_request skcipher_req; + } cra_u; + + /* req ctx trails this struct */ +}; + +/** + * struct af_alg_ctx - definition of the crypto context + * + * The crypto context tracks the input data during the lifetime of an AF_ALG + * socket. + * + * @tsgl_list: Link to TX SGL + * @iv: IV for cipher operation + * @aead_assoclen: Length of AAD for AEAD cipher operations + * @completion: Work queue for synchronous operation + * @used: TX bytes sent to kernel. This variable is used to + * ensure that user space cannot cause the kernel + * to allocate too much memory in sendmsg operation. + * @rcvused: Total RX bytes to be filled by kernel. This variable + * is used to ensure user space cannot cause the kernel + * to allocate too much memory in a recvmsg operation. + * @more: More data to be expected from user space? + * @merge: Shall new data from user space be merged into existing + * SG? + * @enc: Cryptographic operation to be performed when + * recvmsg is invoked. + * @len: Length of memory allocated for this data structure. + */ +struct af_alg_ctx { + struct list_head tsgl_list; + + void *iv; + size_t aead_assoclen; + + struct af_alg_completion completion; + + size_t used; + size_t rcvused; + + bool more; + bool merge; + bool enc; + + unsigned int len; +}; + int af_alg_register_type(const struct af_alg_type *type); int af_alg_unregister_type(const struct af_alg_type *type); @@ -94,4 +190,78 @@ static inline void af_alg_init_completion(struct af_alg_completion *completion) init_completion(&completion->completion); } +/** + * Size of available buffer for sending data from user space to kernel. + * + * @sk socket of connection to user space + * @return number of bytes still available + */ +static inline int af_alg_sndbuf(struct sock *sk) +{ + struct alg_sock *ask = alg_sk(sk); + struct af_alg_ctx *ctx = ask->private; + + return max_t(int, max_t(int, sk->sk_sndbuf & PAGE_MASK, PAGE_SIZE) - + ctx->used, 0); +} + +/** + * Can the send buffer still be written to? + * + * @sk socket of connection to user space + * @return true => writable, false => not writable + */ +static inline bool af_alg_writable(struct sock *sk) +{ + return PAGE_SIZE <= af_alg_sndbuf(sk); +} + +/** + * Size of available buffer used by kernel for the RX user space operation. + * + * @sk socket of connection to user space + * @return number of bytes still available + */ +static inline int af_alg_rcvbuf(struct sock *sk) +{ + struct alg_sock *ask = alg_sk(sk); + struct af_alg_ctx *ctx = ask->private; + + return max_t(int, max_t(int, sk->sk_rcvbuf & PAGE_MASK, PAGE_SIZE) - + ctx->rcvused, 0); +} + +/** + * Can the RX buffer still be written to? + * + * @sk socket of connection to user space + * @return true => writable, false => not writable + */ +static inline bool af_alg_readable(struct sock *sk) +{ + return PAGE_SIZE <= af_alg_rcvbuf(sk); +} + +int af_alg_alloc_tsgl(struct sock *sk); +unsigned int af_alg_count_tsgl(struct sock *sk, size_t bytes, size_t offset); +void af_alg_pull_tsgl(struct sock *sk, size_t used, struct scatterlist *dst, + size_t dst_offset); +void af_alg_free_areq_sgls(struct af_alg_async_req *areq); +int af_alg_wait_for_wmem(struct sock *sk, unsigned int flags); +void af_alg_wmem_wakeup(struct sock *sk); +int af_alg_wait_for_data(struct sock *sk, unsigned flags); +void af_alg_data_wakeup(struct sock *sk); +int af_alg_sendmsg(struct socket *sock, struct msghdr *msg, size_t size, + unsigned int ivsize); +ssize_t af_alg_sendpage(struct socket *sock, struct page *page, + int offset, size_t size, int flags); +void af_alg_async_cb(struct crypto_async_request *_req, int err); +unsigned int af_alg_poll(struct file *file, struct socket *sock, + poll_table *wait); +struct af_alg_async_req *af_alg_alloc_areq(struct sock *sk, + unsigned int areqlen); +int af_alg_get_rsgl(struct sock *sk, struct msghdr *msg, int flags, + struct af_alg_async_req *areq, size_t maxsize, + size_t *outlen); + #endif /* _CRYPTO_IF_ALG_H */ |